A number of the account *actively pro* federating are quite large (like, follower counts in the 1000s or more), and I believe that the reason they want access to Threads here is to increase their reach.
In some ways, this means they're a bit like a corporation themselves - anyone with that many followers isn't moderating them - with the best will in the world, you can't - and they'll have reasons to want to extend their reach - monetary or otherwise.
It seems to me, to be very bad faith given everything we *know* will come if we federate with Threads.